We entered a contract for a new "spec" home in a Desert Ridge community in March 2010 about 6 weeks before its completion and moved in end of April 2010. It was professionally designed and included every upgrade except wood floors-- it has tumbled travertine showers with glass doors, a spiral staircase, granite, 18" tile floors, show piece soaking tub, HUGE corner lot with no neighbors behind us, etc. for $485k in April 2010. Our neighbor across the street just bought the EXACT same model (on a smaller, not corner lot) for $522k and the house next to us, a slightly larger model, just closed for $541k. So as for houses "plummeting" in Desert Ridge, I don't know where. Maybe the houses whose buyer's needed a tax credit to afford the home are plummeting, but I'm not seeing it in our community. People are spending over a half million on homes and then adding $50-$100k worth of pools, turf, outdoor fireplaces, BBQ's, etc. with cash; the builder doesn't let you include pools in the purchase price of the home so you aren't "upside down" on Day 1. We just broke ground on our pool this week and feel fine that we won't be upside down. So either I'm just a more positive person not wanting to jump on the "doom and gloom" train or the answer to your question is-- it depends which community and how good of a deal you can negotiate on a new home.
If you're buying a house for lifestyle, don't worry if the value moves up and down every month-- just buy what you like and what suits you. We own two other houses in Scottsdale and Tempe that we are underwater on and it's not the end of the world.... Houses are meant to lived in and create memories -- People who are trying to time the market perfectly to maximize their investment return should switch to day-trading in the stock market!! :)
P.S. We also looked in Aviano and at the time we were looking (March/April 2010) there were almost no houses left in Aviano that weren't under contract-- our realtor felt bad their nothing left to show us! We satyed away from short sales though, as we learned our lesson after trying to purchase a home in DC Ranch and another house in Scottsdale where we put in the highest offer and still didn't get it. That's why going with a new house was a much better option-- we could control the outcome. But if you have patience and no timelines, a short-sale resale may be for you! Good luck!